A group of people traveling together in the same vehicle may rely on one person's mobile device to download, from a service provider, navigation data that provides directions to a certain destination. If that person's mobile device runs out of battery, then another person's mobile device may need to be used instead. However, the new mobile device may not necessarily have data coverage, and even if it does, it would need to re-download the navigation data from its own service provider, thereby causing the new mobile device to incur data charges for the same navigation data. The same problem would occur if the group decides to travel in different vehicles. In such a scenario, a mobile device for each vehicle would need to separately download the navigation data from its respective service provider, thereby causing multiple data charges to be incurred for downloading the same navigation data.